Abstract: In a method for processing granulate and/or pulverulent polymer with pulverulent additives in an injection moulding machine having a screw with a feed zone of constant screw core diameter, and intermediate zone with a compression and metering section and a mixing element array, with regard to particularly economic processing to high quality injection mouldings the polymer and the pulverulent additives are introduced without previous preparation directly into the feed zone of the screw and in the feed zone the polymer is thoroughly mixed with the pulverulent additives at least twice by means of mixing element arrays, the working length of the screw for the processing having at least 19 times the screw diameter.